1. Field of the Invention
The present invention relates to modular jacks. More specifically, the present invention relates to modular jacks in which a contact array of the modular jack may be easily removed and replaced.
2. Description of the Related Art
Modular connectors are used in computer, telecommunication, data transmission networks, and other similar networks as an input/output connection or interface between communication lines or electronic equipment of the networks. Common modular connectors include RJ-11 and RJ-45 connectors, for example. Modular connectors include a female portion, referred to as a modular jack, and a male portion, referred to as a modular plug.
A conventional modular jack includes a housing having a socket arranged to receive the modular plug. The modular jack is typically permanently mounted to a circuit board such that the modular plug may be easily inserted into the socket and easily disconnected from the socket. When the modular plug is inserted into the socket of the modular jack, the wires or contacts in the modular plug make electrical contact with a metal wire contact array arranged within the housing of the modular jack. The terminals of the contact array are often directly inserted into and soldered to the circuit board. A modular plug may be inserted into and disconnected from a modular jack (referred to as “a mating cycle”) many times.
Over the life of the modular jack, the contact array within the housing will be become worn and damaged by frequent insertions and disconnections of the modular plug into and from the socket. For example, 5,000 mating cycles has conventionally been the upper limit for high quality modular jacks.
Because conventional contact arrays have been integral with the modular jack housing, the entire modular jack must be replaced when the contact array becomes worn or damaged. Replacing the entire modular jack is a labor intensive and costly process.
Conventionally, replacing the modular jack included returning the entire product having the modular jack to a repair facility. Technicians had to disassemble the product, isolate the bad jack, unsolder the modular jack with special equipment, clean and prepare the circuit board, place the new modular jack on the circuit board, resolder, reassemble the end product, and test the new modular jack. Frequently, because of the time and cost of this process, the product was scrapped rather than performing such a costly, difficult and labor-intensive repair.
Attempts have been made to extend the life of the modular jack by using a conductive lubricant between the contact array and the modular plug and by plating the contact array with exotic metals. Neither of these options has satisfactorily extended the life of the modular jack.
In extreme cases where reliability is critical, the modular jack may be contained within a disconnectable module for convenient replacement. Here, the product must be specially designed to accommodate a module utilizing additional connectors and enhanced packaging, resulting in far higher costs. Replacing the disconnectable module includes replacing the entire modular jack, resulting in replacing parts of the modular jack that are not worn or damaged, further increasing costs.
Modular jacks are also used as test ports in electronic equipment. Diagnostic data (usually 500 MHz, or less) are transmitted through a test circuit, the modular jack mounted on a circuit board, and a cable connected to an analyzer to study the electronic equipment. When not in use, the modular jack connected to the test circuit becomes an electrical stub. The electrical stub radiates unwanted radio frequency emissions causing several EMI/RFI (Electro Magnetic Interference/Radio Frequency Interference) problems, which can cause the electronic equipment to fail FCC emissions tests. The worst offending electrical stub is often an unmated modular jack because it is free-standing and because the contacts of the contact array are no longer coupled to and protected by ground planes within the circuit board. Further, the contact array resides in a port opening in the electronic equipment's exterior case. This is a worst case scenario for unwanted EMI/RFI noise propagation.
Permanently mounted modular jacks may also lead to loss of costly or sensitive data due to easy access to the data port. Conventional protective measures, including port covers for blocking plug entry, electronics to disrupt signal transmission, and non-standard keying, all generate higher costs and manufacturing times. Furthermore, the contact array within the modular jack may act as an antenna radiating radio frequencies that may be intercepted with electronic eavesdropping equipment.